Apparatus for burning wood refuse



Aug. 27, 1957 E. 'r. DOUGLASS, JR 2,804,031

APPARATUS FOR BURNING woon REFUSE Filed Dec. 14, 1953 2 Sheets-Sheet 1 INVENTOR.

EDWARb TIDOUGLASS JR.

BY M l M ATTORNEYS Aug. 27, 1957 E. 'r. DOUGLASS, JR 2,804,031

' APPARATUS FOR BURNING woon REFUSE Filed Dec. 14, 1953 2 Sheets-Sheet 2 INVENTOR. EDWARD "r: DOuGLASS JR. BY i 1c M A T "I'ORNEYB APPARATUS FOR BURNING WOOD REFUSE Edward T. Douglass, Jr., Birmingham, Ala. Application December 14, 1953, Serial No. 397,889

3 Claims. (Cl. 11018) This invention relates to an incinerator for relatively light combustible waste such as is formed around cotton mills, peanut processing plants, saw mills, planing mills and woodworking shops and the like, and has for an object the provision of apparatus of the character designated which shall include improved means for supplying air for combustion and for cooling and arresting sparks resulting from the combustion of the waste.

A more particular object of my invention is to provide a waste incinerator including a combustion chamber and a stack and which shall include forced draft means supplying air for combustion, together with means for in- Patent ducing a stream of cold air into the stack for breaking the draft and chilling and extinguishing the sparks passing up the stack.

A still further object of my invention is to provide a waste incinerator including a combustion chamber, a stack, and forced draft means for supplying air for combustion, wherein air together with sparks is drawn from around the top of the stack and passes downward and back into the combustion chamber, thereby preventing the discharge of sparks onto the area around the stack.

As is well known in the art to which my invention relates, the burning of combustible waste such as wood waste around saw mills and other wood working plants entails considerable fire hazard due to hot cinders and burning waste carried upward with the draft and falling in such a way as to set fire to combustible material and structures in the vicinity. For this reason such incinerators have heretofore been located at considerable distances from other structures, thereby requiring additional power for conveying the waste to the incinerator and occupying valuable space which could be used profitably for other purposes. It is accordingly a prime object of my invention to provide an incinerator which shall be capable of efiecting complete combustion of the waste without throwing out hot sparks and burning waste.

In accordance with my invention I provide a relatively large diameter cylindrical structure which may be forty or more feet in height, the lower portion of which forms a combustion chamber and the upper portion a stack. Waste is fed into the lower end of the combustion chamber. A part of the air for combustion is blown tangentially into the lower end of the combustion chamber and is employed to aspirate air from around the upper end of the stack and thus induce the entrainment of sparks from the upper end of the stack and discharge them through suitable openings into the combustion chamber. The remaining air required for combustion is induced through dampered openings in the lower end of the structure. In addition, I provide, openings into the stack at the upper end of the combustion chamber through which air is drawn for chilling the gases of combustion and reducing upward draft in the stack.

Apparatus embodying features of my invention is illustrated in the accompanying drawing forming a part of this application, in which:

Fig. 1 is a somewhat diagrammatic vertical sectional view with parts broken away;

2,804,031 Patented Aug. 27, 1957 Figs. 2, 3, 4 and 5 are sectional views taken respec tively along the lines II-II, IIIIII, IV-IV and V.--V of Fig. 1;

Fig. 6 is a detail sectional view showing the connection between one of the downwardly extending conduits and the opening for admitting air to the combustion chamber;

Fig. 7 is a detail sectional view of one of the air inlet openings; and,

Fig. 8 is an enlarged detail sectional view showing the upper end of the stack.

Referring now to the drawings for a better understanding of my invention, my improved refuse burner comprises a chimney-like structure in which the lower portion 10 forms a combustion chamber and the upper portion 11 forms a stack. The lower portion 10 may extend upwardly somewhat more than half the height of the structure. Between the lower portion 10 andthe upper portion 11 there are provided a plurality of tangentially inclined openings 12, the purpose of which will be described later. The lower portion 10, or combustion chamber, is provided with a refractory lining 13 and an outer steel shell 15. I may also provide an insulating layer 20 of asbestos ,fiber or the like between the shell 15 and the refractory lining 13. In the lower end of the combustion chamber are provided a circumferential series of tangential openings 14, each provided with a damper 14a through which air for combustion passes. A clean out opening 9 is also provided in the lower end of the combustion chamber. A second circumferential series of tangential openings 25 in the lower end of the combustion chamber, above the openings 14, are supplied with air through branch pipes 16a from a bustle pipe 16 which surrounds the lower end of the combustion chamber.

The upper, or stack portion 11 of my improved refuse burner may comprise an outer shell wall 17 and an inner or stack wall 18, and defining between them an annular chamber 19 which is open at the bottom for the passage of cooling air around the inner shell. As shown in Fig. 1 of the drawing, the inner wall 18 terminates at a lower level than the outer wall 17. Extending downwardly through the annular chamber are a plurality of conduits 21 which flare outwardly at the top to provide wide openings 22 which join each other laterally at the top. Mounted on top of the stack by means of brackets 17a is a ring 17b which supports a hemispherical spark arresting screen 170.

Each of the conduits 21 extends outwardly of the stack portion at the lower end thereof as shown at 23 and thence downwardly outside the combustion chamber 10 to join one of the branch pipes 16a supplying over fire air to one of the tangential openings 25. The conduits 21 are each joined to its branch pipe 16a by means of a divided T-fitting 35 which may be rectangular in cross section and which has mounted therein an adjustable vane 31. The vane 31 is pivoted on its upstream side at 32 and has connected thereto an arm 33, outside the fitting. By means of the arms 33 and cooperating quadrants 34 the positions of the vanes 31 may be varied to create and regulate suction downwardly through the conduits 21 and the amount of overfeed air blown into the combustion chamber 10 above the fire. A blower 24 discharges air into the bustle pipe 16 through a conduit 27 and thence through the branch pipes 16a and openings. 25 to furnish over fire air for combustion.

At 26 I show a cyclone separator such as is commonly used around sawmills and woodworking shops for collecting wood waste and which discharges the waste through a conduit 28 and opening 29 into the lower end of the combustion chamber.

From the foregoing description, the operation of my improved refuse burner will be readily understood. Fuel fed into the lower end of the combustion chamber is. burned, air for the combustion being provided through.

3 the openings 14 and by the blower 24 through the tangential openings 25 above the fire thus imparting to the air and to the fuel a circular motion in the lower end of.the combustionchamber. .As the. combustion v gases moveupwardly through the chimney like structure, .cold air is induced into the chimney through the tangentially inclinedopenings .12 which serves .to chill1the,,ga se s -and sparks;.,passing upwardly, 'reducesthe ,draft and accelerates the circular motion of the, gases. .Preferably .each ofthe openings 12 is provided with a damper 12a to regulate the inflow of air therethrough. By reason of the adjustable vanes 31 in the T-fittings 35 downward suction is created in the conduits 21. ,Inasmucha's the inner wall 18 of.the .upperor stackportionterminates belowthe level of.the outer wall 17,,it will be, seen .that some ofithe combustion gases ,togetherwith sparks will be drawn into the vconduits 21 and carried downwardly to bje-reinjected into .the combustion chamber. This insuresfcompleteburning of the sparks before they are finally. discharged.

Fromthe foregoing it will be apparent that I have devisedran improved incinerator which is simple of design, and of manufacture and one which insures athorough combustion of the waste without danger to surrounding structures.

While I have shown my invention in but one form, it will be obvious to those skilled in the artthat it is not so limited, but is susceptible of various changes and. modifications without departing from the spirit thereof, and I desire, therefore, that only such limitations shall be placed thereupon as are specifically setforth in the appended claims.

What I claim is:

1. Apparatus for burning wood refusecomprising an unobstructed cylindrical chimney-shaped combustion chamber, a stack on top of the combustion chamber, there being openings around the lower end of the combustion chamber for the admission of combustion air, means to feed material to be burned into the combustion chamber, a blower discharging air into the combustion chamber above the first mentioned openings, means formiug tangential openings for the admission of air into the stack adjacent its juncture with the combustion chamber thereby to impart an upward, spiral movement to the ascending gases and sparks, a down-coming conduit on the outside of the combustion chamber and stack providing a connection between the blower and the upper end of the stack disposed to withdraw gases and sparks from around the upper end of the stack and return them to the combustion chamber, and means adjacent the upper end of'the stack effective to direct the sparks into the down-coming conduit.

2. In apparatus for burning wood refuse, an'unobstructed chimney-shaped structure having in its lower portion a combustion chamber, there being two series of tangential openings one above the other into the lower end of the combustion chamber, a stack on top of the combustion chamber having tangential openings extending through the wall thereof and disposed to admit air into the interior of the structure at the juncture of the combustion chamber and the stack thereby imparting an upward, spiral movement to the ascending gases and sparks as they enter the bottom of the stack, an outer wall surrounding the upper end of the stack and defining an annular chamber therearound, a blower disposed to discharge air through the upper series of tangential openings in the combustion chamber, and aspirating means actuated by the blower for withdrawing gases and sparks from the annular chamber and discharging them through said upper series of tangential openings.

3.- In apparatus. for burning wood refuse a chimneyshaped combustion chamber, a stackon top of the combustion chamber, means forming tangential openings for the admission of air into the stack adjacent its juncture with the combustion chamber thereby to impart an upward, spiral movement to the ascending gases and sparks, means to 'feed material to be burned into the combustion chamber, there being tangential openings provided in the lower end of the combustion chamber to .supply air for combustion thereinto, a plurality of conduits in communication with the stack adjacent the upper end thereof and extending downwardly outside of the stack and combustion chamber, means adjacent the upper end of the stack effective to direct the sparks into the conduits, suction means connected to each conduit to withdraw gases and sparks from around the upper end of the stack, and means to discharge the gases'and sparks thus withdrawn into the combustion chamber.

References Cited in the file of this patent UNITED STA ES PATENTS 195,495 English Sept. 25, 1877 472,981 Burden Apr. 19, 1892 744,131 Toohey Nov. 17, 1903 1,278,937 Johnson Sept. 17,1918 1,462,720 Rees July 24, 1923 1,496,900 Mitchell June 10, 1924 1,531,766 lTrimborn Mar. 31, 1925 1,860,366 .Lucke May 31, 1932 2,387,005 Boedecker Oct. 16, 1945 2,504,991 Letuin Apr. 25,1950 2,666,403 Polk Jan. 19, 1 954 FOREIGN PATENTS 253,322 Great Britain June 17, 1926 

